If I was in his shoes I would try to get original jurisdiction in the Supreme Court, which I staffed, and cross my fingers for a ruling in my favor if we can get the thinnest constitutional or procedural argument.
Of course I would kick myself for not appointing extremely party people as Supreme Court judges throughout my first term, but there is still a chance the ones I did appoint will rule on party lines, for the argument presented by the party.
That would squash all subsequent constitutional challenges across the republic, leaving the people with a need to gain 75% consensus amongst all of the state's legislatures for a constitutional amendment to overrule a supreme court ruling. Since that won't happen, a path of less resistance would be followed in either scenario:
Congress could still impeach and remove if the Senate consensus changed. So people on the right are really voting for Nancy Pelosi due to her place in the line of succession, if Democrats take the Senate.
Oh right, the people. Eh, I guess a few cities will flare up with nightly battles for month and we'll just keep avoiding the term civil war, and it'll be pretty boring in the vast vast majority of the landmass.